For 35 years, fragments of novelty Garfield telephones have washed up on the picturesque Iroise coast of Brittany almost every day.

Nobody has known why or where they come from; day after day, locals clearing up litter along the Atlantic beaches of the Finistère region, have stumbled across bright orange pieces of feline-shaped plastic.

Sometimes it was just the grinning face or the eyes – designed to open when anyone picked up the receiver. Other times, a headless orange fat torso complete with curly wire, dialpad and plug.

Now the mystery of les téléphones Garfield has been solved by volunteers from the environmental group Ar Viltansou.

As many suspected, the telephones come from a lost container reportedly swept off a cargo ship in 1983. After a local farmer remembered the first Garfield phone appearing after storm that year, he showed the group’s president, Claire Simonin-Le Meur, where they were appearing: a secluded coastal cave deep in the cliffs at Plouarzel accessible only at low tide, but which spat out the telephones at high tide.

“We found this incredible cave, that was 30 metres deep and right at the end the remains of the container,” Simonin-Le Meur, told Euronews. “At the cave opening there was a Garfield lodged in the roof, so we knew we weren’t mistaken and this was where they were.”

Fabien Boileau, the director of the Natural Sea Park of Iroise, also visited the cave, but said the mystery was only partly solved. “We have no idea what happened at the time, where it came from, what ship it was or if one or several containers fell in the sea,” Boileau said.

The lazy and lasagne-loving cartoon cat Garfield was created in 1978 by American Jim Davis for a comic-strip. It has since featured in films and TV series.

Unfortunately, the container remains partly buried and inaccessible so nobody knows how many telephones it still contains. However, it is unlikely the beach cleaners of Iroise have seen the last of Garfield.